The big squeeze on small-business financing continues, despite the overall loosening of U.S. Small Business Administration-backed loans in recent months, two new studies show.Nearly four in 10 small-business owners polled in the past few weeks said they are not able to get the financing they need to run their firms, according to a study Wednesday from the National Small Business Association. That’s up from a third in December 2008.

A report from the Service Employees International Union, also out Wednesday, says SBA lending by major banks has significantly dried up. Bank of America, for instance, made a mere $10 million in 7(a) loans for the first seven months of fiscal year 2009. For the past two full years, it made $102 million and $336 million in 7(a) loans, according to the SEIU.

The 7(a) program provides capital for a range of business purposes, such as construction or supplies.

BofA declined to comment on 7(a) lending numbers but stated in its second-quarter earnings report that its small-business banking division provided more than $580 million in new credit by way of credit cards, loans and lines of credit to more than 35,000 customers.

While SEIU’s report covered other banks, much of it is focused on BofA, because it has “the broadest footprint of any bank,” says Stephen Lerner, assistant to the SEIU president. His group is pushing workers, including bank employees, to unionize.

Today’s reports are gloomy, but there are bright spots on the lending front. From Feb. 17 to July 10, more than 700 lenders that had not made a 7(a) loan since October 2008 made such loans, according to the SBA.

Yet the numbers remain down vs. last year. SBA 7(a) lending for the fiscal third quarter ended in June dropped 38% by volume and 50% by number of loans compared with the same quarter last year, according to the Coleman Report, which provides information on small-business lending.

In addition to SBA loan issues, small businesses are dealing with “worsening credit card terms,” as well as arbitrary reductions in their credit card limits, the NSBA report says.

Rick Snow, co-owner of indoor go-cart business Maine Indoor Karting, says American Express recently cut the credit limit on his OPEN small-business credit card to $3,500 from $10,000. Snow and his wife, also a co-owner, are using their personal credit cards to help cover business costs.

While they have the stress of paying for expenses such as gas, Snow says, there’s much more at stake than just keeping the go-carts going.

“There are 13 families depending on (the employment) we provide,” he says. “That’s significant.”